The present invention relates to electric motors and more particularly to electric motors of the type exposed to ambient entrained particulate materials, such as those motors used with laundry drying machines which are exposed to ambient conditions including immoderate quantities of clothing lint.
It is generally well known in the electric motor art to provide some type of fan assembly within the motor frame structure to cool the windings of the motor by blowing an air stream thereover during motor operations. It also is known to provide external traps on the motor frame structure to stop ambient entrained particulate materials from entering into the motor where such materials reduce motor cooling and operational efficiency and ultimately reduce overall motor life. One such structural arrangement for a motor can be found in U.S. Pat. No. 3,916,232, issued to Michael R. Barone on Oct. 28, 1975. This patent discloses two cooperative sets of metallic annularly disposed vanes which are generally parallel to each other and which are incorporated as part of the rotor itself, one set of the vanes being part of at least one of the rotor end rings and the other set being formed from an annulus secured to the ends of the vanes of the set formed form the rotor end rings.
The present invention recognizes that the prior art motor cooling assemblies have been comparatively expensive in both manufacture and assembly and have presented problems in operation and maintenance, limiting the motor life expectancy through undesirable build-up in the motor parts of particulate matters such as lint, which lint not only absorbs some of the motor lubricant required for desirable bearing performance but also covers portions of the windings to create a heat transfer barrier to the air cooling stream passed thereover.
The present invention, recognizing these aforementioned problems with prior art structures, teaches a unique, novel, comparatively inexpensive to manufacture, assemble and maintain motor cooling and particulate trapping structure, providing for a substantially improved air flow cooling stream which passes over the peripheral surface of a motor stator and end turns and exiting in radially outward fashion away from such stator and end turns. Further, the novel structure of the present invention serves to minimize particulate accumulation at select labyrinth formed areas of the motor, thus reducing oil loss and undesirable blanketing of motor parts with its concomitant reduction of heat transfer function. Not only does the structure of the present invention provide a comparatively improved motor cooling effect along with reduced problems of particulate contamination, but, in addition, the structure of the present invention allows this to be accomplished through either an inexpensive to manufacture and easy to assemble and maintain, integral, unitary arrangement or through one or two separate units which can be proximally positioned to achieve similarly desirable results--the particular arrangement to be utilized depending upon the nature of the environment with which the motor is to be confronted.
Various other features of the inventive structure disclosed herein will become obvious to one skilled in the art upon reading the disclosure herein.